Compensating system.



PATENTED SEPT. 15, 1903.

F. G. BAUM.

GOMPENSATING SYSTEM.

APPLICATION FILED 0GT.17, 1902.

EJ/O/ I FRANK G. BAuM,

UNITED STATES Patented September 15, 1903. Q.

PATE T OFFICE.

FRANK GEORGE BAUM, OF PALOALTO, CALIFORNIA, ASSIGNOR TOv STANLEYELECTRIC MANUFACTURING COMPANY, OF PITTSFIELD, MASSACHU- SETTS, ACORPORATION OF NEl/V JERSEY.

COMPENSATI NG SYSTEM.

SPECIFICATION forming part of Letters Patent No. 738,757, datedSeptember 15, 1903.

Application filed October 17, 1902. Serial No. 127.712. (No model.)

To all whom it may concern:

Be it known that I, FRANK GEORGE BAUM, a citizen of the United States,residing at Palo Alto, countyof Santa Clara, State of California, haveinvented certain new and useful Improvements in Compensating Systems, ofwhich the followingis a full, clear, and exact description.

My improvements relate to compensating systems, and have for theirobject to produce a new and improved system in which the lag in thecurrent of an alternating-current generator is compensated for whenthere are variations in the inductive load; and it consists in IS thematters herein specified.

The following is a description of my invention, reference being had tothe acoompanying drawings, in whieh- Figure 1 representsdiagrammatically a sys- 2o tem embodying my invention. Fig. 2 is adiagram representing electromotive forces and currents. Fig. 3represents diagrammatically a modification of my system.

Referring more particularly to the draw- 2 5 ings, G represents atwo-pole alternatingcurrent generator supplying motors M M and having anexciting-coil F.

E represents an exciter having afield-coil F supplying the field-coil Fof the genera- A is an auxiliary exeiter supplying the fieldcoil F whichis also upon the field-magnet of the exciter E. The armature B of theauxiliary exciter A supplies a direct current.

The field-magnet O of this auxiliary exciter is energized by the coil1), which is supplied bycurrent from the transformer T. The pas sage ofthis current through the coil D is controlled by the rings H and I, asfollows: H is a semicircular conducting-ring, upon which bears the brushJ. I is a continuous conducting-ring, upon which bears the brush K.These rings are mounted so as to revolve synchronously with thegenerator G, the ring H 5 .being so placed that when there is no lag inthe current supplied by the generator G the brush J is in contacttherewith from a little ahead of one maximum to a little ahead of thenext succeeding maximum-that is, so

that the rectified voltage obtained will com- 0 pensate for the drop inpressure in the generator and its connected line at non-inductive load.This is represented in Fig. 2, in which 0 represents the wave of thecurrent supplied by the generator G through the transformer T, and Hrepresents the position of the ring H relatively thereto when the loadis non-inductive Under these circumstances it will be seen that theportion of the currentwave from a little aheadof the points 0 and O willbe impressed upon the coil D of the auxiliary generatorA. If new thecurrentO in the circuit of the main generator lags, the effect is thesame as though the semicircular ring H were advanced relatively to thecur- 6 5' is, has a negative lag of ninety degrees--the relation will beshown by the line H of Fig. 2, in which case the part of the wavebetween. the lines 0 O willbe impressed upon the field-magnet of theauxiliary exciter A, producing an opposite polarity from that producedwhen the lag of the main current is a positive lag. By this means thelag in the circuit of the main generator automatically acts upon theauxiliary exciter A to impress upon the main exciter E, and through itupon the field of the generator G, a magnetizing force which compensatesfor the eifeot of the lag upon the generator G and does this withoutregard to whether the lag is positive or negative.

In the above-described arrangement the electromotive force isintermittently impressed upon the coil D. In the second form (shown inFig. 3) an electromotive force is im- 9 5 pressed upon the coil D allthe time, this being brought about by using an additional seg ment h andmaking the brush K bear upon the cylinder thus formed instead of uponthe continuous ring. The brushes K and h are spaced one hundred andeighty electrical degrees. The segments 1-1 h are separately connectedto the collecting-rings I 1 which by means of brushes '5 t are connectedto the terminals of the coil D. In this way substantially the sameresults are obtained, with the additional result that compensatingcurrent is supplied to the field of the auxiliary exciter continuously.

R is a rheostat in the field-circuit of the exciter A.

It is clear that while I have shown specific embodiments of my inventionmy invention is broader than such specific embodiments, and therefore Ido not desire to be limited to the same or to the particular detailsshown and described. For example, in the modifications shown in Fig. 3the transformer T may be omitted, if desired, and the current of themain circuit used directly upon the fieldcoil of the auxiliary exciter,but I prefer the arrangement shown.

Vhat I claim is- 1. The combination of a main alternatingcurrentgenerator, an exciter therefor, an auxiliary exciter having its fieldenergized by a circuit' having a substantially constant current relationto that of the main circuit, and means for directing thecurrentgenerated by the auxiliary exciter through a field-winding of the mainexciter.

2. The combination of a main alternatingcurrent generator, an exci tertherefor, an an xiliary exciter having its field energized by a circuitin inductive relation to that of the main circuit, and means fordirecting the current produced by the auxiliary exciter through afield-winding of the main exciter.

3. The combination of a main alternatingcurrent generator, an excitertherefor, an auxiliary exciter, a circuit for energizing the auxiliaryexciter having a substantially constant current relation to that of themain circuit, means for dividing each cycle of said energizing-eurrentto increase the energizing effect as the current of the main circuitlags, and means for directing the current generated by the auxiliaryexciter through a fieldwinding of the main exciter.

4. The combination of a main alternatingcurrent generator, an excitertherefor, an auxiliary excite r, a transformer in series with the maincircuit, a circuit supplied by said transformer for exciting saidauxiliary exciter and means for directing the current generated by theauxiliary exciter through a field-winding of the main exciter.

5. The combination of a main alternatingcurrent generator, an excitertherefor, an auxiliary exciter, a transformer in series with the maincircuit, a circuit supplied by said transformer for exciting saidauxiliary exciter, means for dividing the cycles in saidenergizing-circuit to increase the energizing effect as the current ofthe main circuit lags, and means for directing the current generated bythe auxiliary exciter through the field-winding of the main exciter.

6. In combination, a main alternating-current generator, a compensatingexciter, a circuit for energizing said exciter supplied from the maincircuit of said main alternating-current generator, and means forimpressing upon said circuit the electromotive forces during one hundredand eighty degrees of the cycle beginning with a little before themaximum voltage of said cycle when the load on the main generator doesnot produce a currentlag.

7. In combination, a main alternating-current generator, a compensatingexciter, a circuit for energizing said exciter supplied from the maincircuit of said main alternating current generator, and a switchdirecting said current so that when the current is non-laggingsubstantially equal and relatively similar parts of successive phasesare impressed upon said exciter, said parts beginning and ending alittle before the positive and negative maxima voltage of each cycle.

8. In combination, a main alternating-current generator, an exciteracting to compensate for lagging currents, a circuit for energizing saidexciter supplied from the main circuit of said main alternating-currentgen erator, and a switch directing said current so that when the currentis non-lagging substantially equal and relatively similar parts ofsuccessive phases are impressed upon said exciter, said parts beginningand ending a little before the positive and negative maxima voltage ofeach cycle, and a second exciter intermediate to said first exciter andsaid generator.

9. In a compensating system, an alternating-current generator, adirecting-switch having members which when the current is non laggingmake contact at a little before one voltage maxim um of each cycle andbreak contact a little before the next succeeding maximum voltage ofeach cycle, and thereby impress relatively the same parts of successivecycles upon an energizing-circuit carrying the current they control.

Signed at Palo Alto, California, this 15th day of September, 1902.

' FRANK GEORGE BAUM.

WVitnesses:

ALBERT W. SMITH, GEO. F. MADDooK.

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